/*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
* Dual licensed under the MIT (MIT_LICENSE.txt)
* and GPL Version 2 (GPL_LICENSE.txt) licenses.
*
* Version: 1.1.1
* Requires jQuery 1.3+
* Docs: http://docs.jquery.com/Plugins/livequery
*/

(function($) {

$.extend($.fn, {
livequery: function(type, fn, fn2) {
var self = this, q;

// Handle different call patterns
if ($.isFunction(type))
fn2 = fn, fn = type, type = undefined;

// See if Live Query already exists
$.each( $.livequery.queries, function(i, query) {
if ( self.selector == query.selector && self.context == query.context &&
type == query.type && (!fn || fn.$lqguid == query.fn.$lqguid) && (!fn2 || fn2.$lqguid == query.fn2.$lqguid) )
// Found the query, exit the each loop
return (q = query) && false;
});

// Create new Live Query if it wasn't found
q = q || new $.livequery(this.selector, this.context, type, fn, fn2);

// Make sure it is running
q.stopped = false;

// Run it immediately for the first time
q.run();

// Contnue the chain
return this;
},

expire: function(type, fn, fn2) {
var self = this;

// Handle different call patterns
if ($.isFunction(type))
fn2 = fn, fn = type, type = undefined;

// Find the Live Query based on arguments and stop it
$.each( $.livequery.queries, function(i, query) {
if ( self.selector == query.selector && self.context == query.context &&
(!type || type == query.type) && (!fn || fn.$lqguid == query.fn.$lqguid) && (!fn2 || fn2.$lqguid == query.fn2.$lqguid) && !this.stopped )
$.livequery.stop(query.id);
});

// Continue the chain
return this;
}
});

$.livequery = function(selector, context, type, fn, fn2) {
this.selector = selector;
this.context = context;
this.type = type;
this.fn = fn;
this.fn2 = fn2;
this.elements = [];
this.stopped = false;

// The id is the index of the Live Query in $.livequery.queries
this.id = $.livequery.queries.push(this)-1;

// Mark the functions for matching later on
fn.$lqguid = fn.$lqguid || $.livequery.guid++;
if (fn2) fn2.$lqguid = fn2.$lqguid || $.livequery.guid++;

// Return the Live Query
return this;
};

$.livequery.prototype = {
stop: function() {
var query = this;

if ( this.type )
// Unbind all bound events
this.elements.unbind(this.type, this.fn);
else if (this.fn2)
// Call the second function for all matched elements
this.elements.each(function(i, el) {
query.fn2.apply(el);
});

// Clear out matched elements
this.elements = [];

// Stop the Live Query from running until restarted
this.stopped = true;
},

run: function() {
// Short-circuit if stopped
if ( this.stopped ) return;
var query = this;

var oEls = this.elements,
els = $(this.selector, this.context),
nEls = els.not(oEls);

// Set elements to the latest set of matched elements
this.elements = els;

if (this.type) {
// Bind events to newly matched elements
nEls.bind(this.type, this.fn);

// Unbind events to elements no longer matched
if (oEls.length > 0)
$.each(oEls, function(i, el) {
if ( $.inArray(el, els) < 0 )
$.event.remove(el, query.type, query.fn);
});
}
else {
// Call the first function for newly matched elements
nEls.each(function() {
query.fn.apply(this);
});

// Call the second function for elements no longer matched
if ( this.fn2 && oEls.length > 0 )
$.each(oEls, function(i, el) {
if ( $.inArray(el, els) < 0 )
query.fn2.apply(el);
});
}
}
};

$.extend($.livequery, {
guid: 0,
queries: [],
queue: [],
running: false,
timeout: null,

checkQueue: function() {
if ( $.livequery.running && $.livequery.queue.length ) {
var length = $.livequery.queue.length;
// Run each Live Query currently in the queue
while ( length-- )
$.livequery.queries[ $.livequery.queue.shift() ].run();
}
},

pause: function() {
// Don't run anymore Live Queries until restarted
$.livequery.running = false;
},

play: function() {
// Restart Live Queries
$.livequery.running = true;
// Request a run of the Live Queries
$.livequery.run();
},

registerPlugin: function() {
$.each( arguments, function(i,n) {
// Short-circuit if the method doesn't exist
if (!$.fn[n]) return;

// Save a reference to the original method
var old = $.fn[n];

// Create a new method
$.fn[n] = function() {
// Call the original method
var r = old.apply(this, arguments);

// Request a run of the Live Queries
$.livequery.run();

// Return the original methods result
return r;
}
});
},

run: function(id) {
if (id != undefined) {
// Put the particular Live Query in the queue if it doesn't already exist
if ( $.inArray(id, $.livequery.queue) < 0 )
$.livequery.queue.push( id );
}
else
// Put each Live Query in the queue if it doesn't already exist
$.each( $.livequery.queries, function(id) {
if ( $.inArray(id, $.livequery.queue) < 0 )
$.livequery.queue.push( id );
});

// Clear timeout if it already exists
if ($.livequery.timeout) clearTimeout($.livequery.timeout);
// Create a timeout to check the queue and actually run the Live Queries
$.livequery.timeout = setTimeout($.livequery.checkQueue, 20);
},

stop: function(id) {
if (id != undefined)
// Stop are particular Live Query
$.livequery.queries[ id ].stop();
else
// Stop all Live Queries
$.each( $.livequery.queries, function(id) {
$.livequery.queries[ id ].stop();
});
}
});

// Register core DOM manipulation methods
$.livequery.registerPlugin('append', 'prepend', 'after', 'before', 'wrap', 'attr', 'removeAttr', 'addClass', 'removeClass', 'toggleClass', 'empty', 'remove', 'html');

// Run Live Queries when the Document is ready
$(function() { $.livequery.play(); });

})(jQuery);